Study of the microstructures of Pb(ZrxTi1-x)/YBa2Cu3O7-delta heterostructural films

The structures of Pb(ZrxTi1-x)O-3/YBa2Cu3O7-delta (PZT/YBCO) bilayer hetero structure with different thicknesses of PZT sublayer were investigated by x -ray high resolution diffraction, small angle reflectivity and reciprocal s pace mapping. The epitaxial films of YBCO and PZT are highly oriented with the SrTiO3 substrate. The lattice parameter, c, of the YBCO layer was found to be c = 11.722 +/- 0.001 Angstrom, which is 0.5% larger than that of the bulk one. The lattice parameter, c, of the PZT layer is c = 4.108 +/- 0.00 1 Angstrom, indicating that the composition of the samples was Pb(Zr0.51Ti0 .49)O-3 The interface roughness of the YBCO/STO and YBCO/PZT, as well as th e surface roughness was obtained. It was found that there existed an undesi gned layer on the top of the PZT layer. The effect of the crystalline quali ty of the STO substrate on the quality of the YBCO and PZT epitaxial films is discussed.